There is known a ‘compressed air engine system and method for generating electrical energy from the controlled release of compressed air’ described in U.S. Pat. No. 5,553,454 (hereby entirely incorporated by reference) to Mortner, as follows: “A system and method is provided for generating electrical energy by operatively connecting a generator to a drive shaft which is rotated axially when fan turbines connected to the drive shaft are rotated. The turbines are rotated by directing the release of air under pressure toward a plurality of blade surfaces of the turbines. The air under pressure is supplied from a plurality of storage tanks which are connected to one of a pair of pressure guide rings, which guide rings receive air under pressure from one or more connected tanks and direct the air through an output duct and toward the blade surfaces. The flow of air under pressure is controlled by a power regulator and controller which monitors the power output from the generator and transmits electrical signals to adjust the open and closed positioning of a tank output valve on each of the plurality of tanks. Alternatively, the drive shaft may be connected to a water pump, evaporating device, or the drive wheels of a motor vehicle for pollution-free powering of that device through the controlled release of compressed air in the plurality of tanks.” The abovementioned method contemplates using the already compressed air from storage tanks, though does not show how to obtain the compressed air.
On the other hand, there exists another problem of reduction of the air resistance experienced by a moving transportation means. A ‘motor vehicle with flow-influencing devices to reduce air resistance’ is taught in U.S. Pat. No. 6,378,932 (hereby entirely incorporated by reference) to Fasel et al: “A motor vehicle has an outer contour around which the headwind flows when driving has associated with it flow-influencing structure to reduce the air resistance of the motor vehicle is known. The flow-influencing structure are movably mounted in a vicinity of the outer contour and can be activated periodically with the aid of drive devices in order to introduce suitably time-dependent disturbances into the flow of the headwind in the vicinity of the flow-influencing structure.” According to Fasel et al, the mentioned means are to reduce the airflow, though they don't teach, whether this airflow could generate energy.
Another example of a device for reducing the air resistance to a moving truck is disclosed in U.S. Pat. No. 6,736,447 (hereby entirely incorporated by reference) to Angelo et al entitled ‘Ducted aerodynamic front section of a vehicle’: “A truck front section (120) including a grill (128), a hood (121), and a bridge assembly (137) is provided. The grill has a substantially vertical front surface and an upper portion. The hood has an upper panel (121) with a sloping front end disposed adjacent the grill upper portion. The bridge assembly is disposed above the front end of the hood upper panel and has a pair of oppositely disposed upright end members (133) attached to the hood upper panel. The bridge assembly also has a substantially horizontal aerodynamically shaped member (138 and/or 140) attached to the end members. The upper portion of the grill, the front end of the hood upper panel and the bridge assembly cooperatively form a duct generally disposed above the grill. The duct may discharge into a longitudinal channel (112 and/or 114) formed in the upper panel.” The ‘Ducted aerodynamic front section’ is also not concerned with generating energy.
As known, the resistance airflow (its pressure can be essentially proportional to the squared speed) may cause about 70-90% (depending on the speed) of losses of power developed by the engine of a transportation means. Therefore, on the one hand, the resistance airflow decelerates the motion of the moving transportation means and consumes an essential portion the engine's fuel that is wasted for overcoming the air resistance. On the other hand, the resistance airflow possesses its own energy that can and should be utilized.